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Early-Type Galaxies * Galaxy Group and Cluster * Star Forming in Galaxies * Active Galactic Nuclei * Really High-Redshift Universe * The Large-Scale Structure and Cosmology Early Type Galaxies Structural Evolution * There is some strong evidence that giant elliptical galaxies grow their extended stellar haloes slowly, through accretion, around a dense, compact core (e.g. van Dokkum et al., 2010; van Dokkum & Conroy, 2012) arXiv:1212.1451 Stellar Population * Difficulties in using alpha/Fe to measure the SF timescale: *# Unknown type Ia SNe delay time distribution. *# Overall SN Ia rate may vary with some systematic way *# Possibility of selective mass-loss such that Fe is preferentially lost from the system *# Potential variation in the IMF ** See: Worthey et al. 1992; Thomas et al. 1999; Trager et al. 2000 ** A promising alternative chronometer is Ba, which is believed to form predominately within the envelopes of asymptotic giant branch (AGB) stars via s''-process neutron captures (Burbidge et al. 1957; Busso et al. 1999; Herwig 2005) ** '''Sr' is another neutron capture element with strong transitions in the blue. Like Ba, Sr is predominantly produced by the s-process, at least in the solar system. These two elements probe two of the three s-process peaks, with Sr belonging to the first (along with Y and Zr), and Ba belonging to the second (along with La, Ce, Pr, and Nd). While the nucleosynthetic origin of Ba is relatively secure, the same cannot be said for the elements in the first s-process peak (Couch et al. 1974; Woosley & Hoffman 1992; Raiteri et al. 1993; Sneden et al. 2008). ** Indeed, current chemical evolution models of the Galaxy are unable to reproduce the observed behavior of Sr-Y-Zr at low metallicity without appealing to exotic and/or ad hoc nucleosynthetic sites (e.g., Travaglio et al. 2004; Qian & Wasserburg 2008) Extragalactic Globular Clusters * GCs around isolated elliptical galaxies: arXiv:1212.1451 *# NGC 720 (Kissler-Patig et al. 1996) *# NGC 821 (Spitler et al. 2008) *# NGC 3585 (Hempel et al. 2007; Humphrey et al. 2009; Lane et al. 2012) *# NGC 3818 (Cho et al. 2012) *# NGC 5812 (Lane et al. 2012) * In many cases it seems that red (metal rich) GC populations may have formed in situ along with the galaxy, while the bluer (more metal poor) GCs arrived later as part of the hierarchical merger process, assuming mainly minor mergers (Lee et al., 2008; Elmegreen et al., 2012) arXiv:1212.1451 * The Washington photometric system (Canterna, 1976) has been chosen as it has the advantage of being a good discriminator between compact blue background galaxies and GC candidates (Dirsch et al., 2003a); Furthermore, an apparently Universal peak exists in the (C−R) colour of old globular cluster populations associated with elliptical galaxies (e.g. Richtler et al., 2012) arXiv:1212.1451 Extragalactic Planetary Nebula * Planetary Nebulae (PNe) in external galaxies are mostly regarded either as tracers of the gravitational potential (e.g Romanowsky et al. 2003; Douglas et al. 2007) or as indicators for the distance of their galactic hosts (e.g., Ciardullo et al. 1989; Jacoby, Ciardullo, & Ford 1990; Jacoby et al. 1992), with the latter advantage owing to the nearly universal – though not fully understood – shape of the PNe ** Extra-galactic PNe luminosity function (PNLF, generally in the IIIλ5007 emission). can also be used as probes of their parent stellar population (e.g., Richer, Stasinka, & McCall 1999; Jacoby & Ciardullo 1999; Dopita et al. 1997) and understanding in particular the origin of the PNLF is a puzzle that, once solved, promises to reveal new clues on the late stages of stellar evolution and on the formation of PNe themselves (see, e.g., Ciardullo 2006). Intra-Cluster Light * Important references: Gregg & West 1998; Mihos et al. 2005; Zibetti et al. 2005; Gonzalez et al. 2007; Krick & Bernstein 2007; Rudick et al. 2010; Burke et al. 2012 * The importance of the ICL in the baryon budget is the subject of current debate: arXiv:1212.1613 *# Krick & Bernstein 2007: 6-22% within 25% of Virial radius *# Gonzalez et al. 2005; 2007: 33% for BCG+ICL within $r_200$ *# McGee & Balogh 2010: ~50% (mapping of hostless SN Ia) *# Zibetti et al. 2005: ~11% within 500kpc (stacking of SDSS cluster) * Its origin at least partly in matter ejections from galaxies during galaxy-galaxy or galaxy-cluster potential interactions (see e.g. Adami et al. 2005b, or Dolag et al. 2010 for recent simulations) High-Redshift Early-Type Galaxies * The quiescent galaxies form a signiﬁcant fraction (30 − 50%) of all massive z~2 galaxies (e.g. Kriek et al. 2006; Williams et al. 2009; Toft et al. 2009) arXiv:1212.1158 Structure and Morphology of Galaxies Bar * Cases where bulges seen in edge-on galaxies have a distinctly "boxy" or even "peanut-shaped" morphology. A series of imaging studies (Jarvis 1986; de Souza & Dos Anjos 1987; Shaw 1987; Dettmar & Barteldrees 1990; Lutticke et al. 2000a ) gradually demonstrated that such structures are actually quite common ** Even the Galaxy's own bulge has turned out to be boxy (e.g., Kent et al. 1991; Dwek et al. 1995) ** The peculiarity is not just morphological: several early stellar-kinematic studies noted that strongly boxy or peanut-shaped bulges exhibited cylindrical stellar rotation (e.g., Bertola & Capaccioli 1977; Kormendy & Illingworth 1982) ** Although several models have been proposed for boxy or peanut-shaped bulges, such as their being the results of minor mergers (e.g., Binney & Petrou 1985), the most successful explanation has come from investigations of bar formation and evolution. A pioneering 3D N-body study by Combes & Sanders (1981) noted that the bars which formed in their simulation showed "a peanut-shape morphology" when the model was viewed edge-on with the bar perpendicular to the line of sight ** In the early 1990s, simulations of galaxy discs clearly showed that a vertically unstable \buckling" phase often followed the formation of a bar (e.g., Combes et al. 1990; Raha et al. 1991); the morphology and cylindrical kinematics of the resulting structure matched observations of boxy and peanutshaped bulges (see Athanassoula 2005 and Debattista et al. 2006 for reviews). ** This rapid, asymmetric buckling phase is usually assumed to be driven by a global bending instability (e.g., Merritt & Sellwood 1994). However, alternate formation mechanisms which involve the resonant heating or trapping of stellar orbits have been suggested (Combes et al. 1990; Quillen 2002; Debattista et al. 2006) ** Other theoretical studies have investigated the underlying orbital structure which may support this morphology (e.g., Pfenniger 1985; Pfenniger & Friedli 1991; Patsis et al. 2002; Martinez-Valpuesta et al. 2006), explored conditions under which it may be promoted or suppressed (e.g., Berentzen et al. 1998; Athanassoula & Misiriotis 2002; Athanassoula 2005; Debattista et al. 2006; Wozniak & Michel-Dansac 2009), and even suggested that multiple phases of buckling and vertical growth can take place (Martinez-Valpuesta et al. 2006). ** Evidence confirming the association of bars with boxy/peanut-shaped (B/P) bulges in real galaxies has come primarily from spectroscopy of edge-on galaxies. The major axis kinematics of ionized gas (Kuijken & Merrifield 1995; Merrifield & Kuijken 1999; Bureau & Freeman 1999; Veilleux et al. 1999) and stars (Chung & Bureau 2004) in edge-on galaxies with boxy or peanut-shaped bulges displays the characteristic imprint of bars, as predicted by orbital analyses and simulations, both pure N-body (Athanassoula & Bureau 1999; Bureau & Athanassoula 2005) and hydrodynamical (e.g., Athanassoula & Bureau 1999). ** In addition, near-IR imaging of edge-on systems indicates that B/P bulges are accompanied by larger-scale extensions in the disc of the galaxy, suggestive of the vertically thin outer zones of bars (Lutticke et al. 2000b; Bureau et al. 2006). The frequency of boxy and peanut-shaped bulges is consistent with most barred galaxies having vertically thickened inner regions (Lutticke et al. 2000a). Galaxy Group and Cluster * First evidence of superclusters as agglomerations of rich clusters of galaxies: Abell 1961 arXiv:1212.1597 ** Superclusters are generally deﬁned as groups of two or more galaxy clusters above a given spatial density enhancement (Bahcall 1988) ** The existence of superclusters was confirmed by: Bogart & Wagoner 1973; Hauser & Peebles 1973; Peebles 1974 ** Catalogs of superclusters: e.g. Rood (1976), Thuan (1980), Bahcall (1984), Batuski & Burns (1985), West (1989), Zucca et al. (1993), Kalinkov & Kuneva (1995), Einasto et al. (1994, 1997, 2001, 2007), and Liivamagi et al. (2012) * The Dressler-Shectman test for substructure in galaxy cluster:(Dressler & Shectman 1988; Halliday et al. 2004) ** {\delta}^2=\frac{11} )^2+({\sigma}_{loc}-{\sigma}_v)^2] ** {\overline{v}} and {\sigma}_v is the mean velocity and velocity dispersion of the cluster. ** v_{loc} and {\sigma}_{loc} is the mean velocity and velocity dispersion of that galaxy and its ten nearest neighbours within the cluster ** The sum of the \delta value of each galaxy, \Delta , gives the measure of the total substructure present in a cluster. * Coincidence between cool X-ray emitting gas and Ha filaments: *# ESO 137-001 in Abell 3627: (Sun et al. 2007 ) *# BCG of Perseus Cluster: (Sanders & Fabian 2007; Fabian et al. 2008, 2011 ) *# BCG of Centaurus Cluster: (Sanders & Fabian 2002, 2008 ) *# Virgo: M87 (Werner et al. 2010, 2012 ); M86 (Ehlert et al. 2012) Environmental Effect on Stars and Gas # '''Ram-pressure Stripping: (Gunn & Gott ) #* Complex physics is required to account for the morphology of the stripped gas tails and their multiwavelength properties (e.g. Roediger & Bruggen 2006, 2007, 2008b; Tonnesen & Bryan 2010; Tonnesen et al. 2011; Tonnesen & Bryan 2012 ) # Viscosity of the ICM: (Roediger & Bruggen 2008a ) # Turbulence and Magnetic Fields: (Ruszkowski et al. 2012 ) Dwarf Galaxies Blue Compact Dwarf Galaxies * Nearby blue compact dwarf galaxies (BCDs) are a unique category of galaxies that have low metallicity and high gas fraction in the nearby Universe (Sargent & Searle 1970; van Zee, Skillman, & Salzer 1998; Kunth & Ostlin 2000 ) **Some BCDs are also experiencing the most active class of star formation with the formation of super star clusters (SSCs) (Turner et al. 1998; Kobulnicky & Johnson 1999 ). ** All these BCDs are also classiﬁed as Wolf-Rayet galaxies: the Wolf-Rayet feature indicates that the typical age of the current starburst is a few Myr (Vacca & Conti 1992; Lopez-Sanchez & Esteban 2010 ) Star Formation in Galaxies High Velocity Clouds * The discovery of HVC: Muller et al. 1966 * Definition: |v_LSR|>90 km/s; (Intermediate Velocity Clouds, IVCs: 40km/s<|v_LSR|<90km/s * Review: Richter 2006; Wakker et al. 1998 ** HVCs span a relatively large range in metallicities from ~0.1 to 1 Solar (Wakker et al. 1999, 2001; Richter et al. 1999, 2001; Gibson et al. 2001; Tripp et al. 2003; Collins et al. 2003; Richter et al. 2005, 2009; Shull et al. 2011), indicating that HVCs and IVCs have various origins. ** Recent distance estimates of several IVCs and HVCs indicate that most of the IVCs appear to be located within 2 kpc from the Galactic disc, in accordance with the scenario that IVCs represent gas structures related to the galactic fountain (Wakker et al. 2008; Smoker et al. 2011). ** Most of the HVCs appear to be located at distances < 20 kpc (Wakker et al. 2007; Thom et al. 2006, Thom et al. 2008) ** HVCs indicate gas circulation processes in the intermediate (d<100kpc) environment of the Milky Way. Their total HI mass is about ~10^8 Msolar; and contribute ~0.7M_solar/yr to the Milky Way's gas-accretion rate (Richter 2012; Wakker 2004 The X_CO Factor * A variety of observations have shown that \alpha\sim4.4 M_{\odot}{pc}^{-2} (K km s^{-1})^{-1} is characteristic of the local area of the Milky Way (Solomon et al. 1987; Strong & Mattox 1996; Abdo et al. 2010) arXiv:1212.1208 * Different techniques to explore the possibility of a changing X_CO across different types of galaxies in nearby Universe: *# These include virial mass measurements of individual GMCs in the Milky Way, the local group, and nearby spirals (e.g. Wilson 1995; Blitz et al. 2007; Bolatto et al. 2008; Fukui & Kawamura 2010, and references therein) *# Estimating the molecular gas mass from dust far-IR emission modeling while constraining the dust-to-gas ratio and the contribution from atomic hydrogen (Israel 1997; Leroy et al. 2011, 2012) *# Using the star formation rate (SFR) under the assumption of a known molecular gas depletion timescale to estimate the amount of H_2 (Schruba et al. 2012; McQuinn et al. 2012). ** X_CO shows higher values for lower metallicity systems. This increase is most likely driven not only by a decrease in the carbon and oxygen abundances, but mainly by a drop in the optical depth within GMCs due to a lower abundance of dust. The CO/C+ dissociation boundary moving inwards within the clouds, leaving behind large envelopes of "CO Dark" molecular gas (e.g Bolatto et al. 1999) ** The molecular gas in merging and starburst galaxies show X_CO value factors of a few lower than the MW value. (Wild et al. 1992; Shier et al. 1994; Mauersberger et al. 1996; Solomon et al. 1997; Downes & Solomon 1998; Bryant & Scoville 1999; Meier et al. 2010) *** This eﬀect is thought to be caused by the impact of higher gas temperatures and stronger turbulence on the brightness temperature of the CO line and the escape probability of CO(1-0) photons. (Shetty et al. 2011) *** The lower X_CO factor is also found in high-redshift "normal" star-forming galaxies (Genzel et al. 2012) arXiv:1212.4152 * A series of studies using analytic models, numerical simulations, and combinations of both, have examined the dependance of X_CO with metallicity, gas temperature, gas dynamics, and the local radiation ﬁeld (e.g. Krumholz et al. 2011; Shetty et al. 2011; Narayanan et al. 2012; Feldmann et al. 2012a) arXiv:1212.4152 * The value of X_CO has been shown to change as a function of galactocentric radius in the MW using a series of diﬀerent techniques: *# Dust emission modeling (Sodroski et al. 1995) *# Measurements of gamma-ray emissivity from cosmic-ray gas interactions (Digel et al. 1996; Strong et al. 2004; Abdo et al. 2010) *# Direct virial mass measurements of GMCs (Arimoto et al. 1996; Oka et al. 1998). arXiv:1212.4152 Star Formation Rate Calibration and Star-Formation Law * Schimdt-Kennicutt law (Schmidt 1959; Kenicutt 1998) ** studies of this law in spatially resolved manner across the disk of nearby galaxies (Kennicutt et al. 2007; Bigiel et al. 2008; Blanc et al. 2009; Verley et al. 2010; Onodera et al. 2010; Schruba et al. 2011; Liu et al. 2011; Rahman et al. 2012) *** About the uncertainty in the slope: (Blanc et al. 2009; Rahman et al. 2012; Calzetti et al. 2012) *** The normalization is consistent with a depletion timescale for molecular gas of ~ 2Gyr at the typical molecular gas surface densities (Leroy et al. 2008; Rahman et al. 2012) * Radio-FIR Correlation: (de Jong et al. 1985; Helou, Soifer & Rowan-Robinson 1985) Active Galactic Nuclei and QSO Black Hole Mass Estimation * The black hole mass is usually estimated using reverberation mapping calibrated scaling relations (the so–called “single epoch virial method”, or SE virial, Peterson 1993; Peterson et al. 2004; Onken et al. 2004; Vestergaard & Peterson 2006; Bentz et al. 2009). arXiv:1212.1181 Relation and Coevolution with Host Galaxy * Correlations between the mass of the central black hole and absolute magnitude (Magorrian et al. 1998; Marconi & Hunt 2003; Häring & Rix 2004 ), and/or stellar velocity dispersion (Gebhardt et al. 2000; Merritt & Ferrarese 2001 ) of the spheroidal component indicate that the mass ratio between a SMBH and its bulge is constant over a wide dynamic range in mass (0.0014) arXiv:1212.2999 * Related Measurements: ** Optical imaging from space with HST can be used to disentangle the light between an AGN and its host galaxy (e.g., Sánchez et al. 2004; Jahnke et al. 2004, 2009; Bennert et al. 2011b; Cisternas et al. 2011 ) ** Measure the stellar velocity dispersion from optical spectra for less luminous AGNs (Woo et al. 2008 ) ** Measure the stellar mass' content of AGN host galaxies through template ﬁtting of the broad-band photometric spectral energy distribution (Merloni et al. 2010; Brusa et al. 2009; Xue et al. 2010 ) ** Bulge luminosity from decomposition (Giavalisco et al. 2004) ** Possible biases originating from selection of AGN (see '' Salviander et al.2007; Lauer et al. 2007'' ) * Offsets from local M_{BH}-M_{Bulge} relation: (see Peng et al. 2006a, b ) ** Evidence for elevated black hole masses as compared to either the bulge component (Woo et al. 2008; Bennert et al. 2011b) or total (Merloni et al. 2010 ) stellar mass of the host galaxy. ** Undermassive bulge ? (Jahnke et al. 2009; Cisternas et al. 2011 ) * Although local early type galaxies and QSOs presented a linear scaling relation of the central black hole masses and the masses of the stellar bulge, which motivated the theoretical perspective on the growth of the central black holes and the host galaxy formation, high redshift QSOs would be the key to a robustic check of the theoretical models (Faber et al. 1997, McLeod & Rieke 1995, Silk & Rees 1998, Wang & Biermann 1998, Wang et al. 2000, 2003, Merrit 1998, Monaco et al. 2000, Bian et al. 2003, Peng et al. 2006, Schramm et al. 2008) Torus, BLR, Nuclear Gas et al. *By means of Adaptive Optics (AO) integral-ﬁeld spectroscopy, Hicks et al. (2009, hereafter H09) showed that the molecular gas in the central tens of parsecs of Seyfert galaxies relates directly to the largest structures associated with the obscuring torus, as predicted by clumpy torus models (e.g., Nenkova et al. 2002, 2008; Schartmann et al. 2008): it is in a rotating disk-like distribution, has a high velocity dispersion relative to rotation (V/σ<1), and is optically thick arXiv:1212.1162 *HCN measurements of Seyfert galaxies suggest that the nuclear dense gas also has a large dispersion (Sani et al. 2012) arXiv:1212.1162 Outflows and Winds * Outflow can be accelerated by : *# magnetocentrifugal forces (Everett 2005; de Kool & Begelman 1995) *# radiation pressure in lines and continuum (Murray et al. 1995; Proga, Stone, & Kallman 2000) *# by thermal pressure force (e.g., Balsara & Krolik 1993; Krolik & Kriss 2001; Chelouche & Netzer 2005). ** The outflowing winds play an important role in three ways: **# the extraction of angular momenta from disks allows accretions to proceed (e.g., Blandford & Payne 1982; Emmering et al. 1992; Konigl & Kartje 1994; Everett 2005), leading to growth of black holes **# the disk outflow also provides energy and momentum feedback to interstellar media of host galaxies and to intergalactic media (IGM), and inhibits star formation activity (e.g., Springel, Di Matteo, & Hernquist 2005) **# outflowing winds may induce the metal enrichment of the IGM (e.g., Hamann, Barlow, & Junkkarinen 1997b; Gabel et al. 2006) * Broad Absorption Line QSO (BALs): are detected in about 10-20% of optically selected quasars (e.g., Hewett & Foltz 2003; Reichard et al. 2003a), and their detection rate is slightly higher in radio-quiet quasars (e.g., Stocke et al. 1992; Becker et al. 2001; Green 2006). ** BALs are thought to originate in the outflowing winds when our sight-line intersects this component. This idea is supported by the fact that there are no significant differences in the properties of quasars with BALs (BAL QSOs) and those without BALs (non-BAL QSOs) (Weymann et al. 1991; Reichard et al. 2003a). ** Moreover, quasar spectra tend to be redder when BAL profiles, especially those with low ionization absorption lines (i.e., LoBALs and FeLoBALs), are observed, which is probably caused by dust reddening in the outflows (e.g., Sprayberry & Foltz 1992; Yamamoto & Vansevicius 1999) Observed Properties * The X-ray/UV ratio (alpha_ox) is found to be strongly anti-correlated with the ultraviolet specific luminosity L_{UV} . (Strateva et al. 2005; Steen et al. 2006; Just et al. 2007; Gibson et al. 2008; Grupe et al. 2010; Vagnetti et al. 2010 ) ** About its dispersion, "artiﬁcial alpha_ox variability" due to non-simultaneity is not the main cause of dispersion (Vagnetti et al. 2010) arXiv:1212.3432 * A subset of active galactic nuclei (AGN) show in their spectra emission lines from very highly ionised atoms, known as Coronal lines (CLs). They are collisionally excited forbidden transitions within low-lying levels of ionised species with ionization potentials IP > 100 eV. CLs have been detected in the optical and infrared spectra of all types of AGN, including Seyfert 1 and Seyfert 2 galaxies, narrow-line Seyfert 1 galaxies, and radio galaxies (e.g., Penston et al. 1984; Marconi et al. 1994; Nagao et al. 2000; Sturm et al. 2002; Rodr´ıguez-Ardila et al. 2002, 2006; Deo et al. 2007; Mullaney & Ward 2008; Komossa et al. 2008; Gelbord et al. 2009) ** The precise nature and origin of CLs are still a matter of debate. Diﬀerent scenarios have been considered in the literature, including: **# Winds from the molecular torus (e.g. Pier & Voit 1995; Nagao et al. 2000; Mullaney et al. 2009) **# (X-ray) ionised absorbers (e.g., Komossa & Fink 1997a,b; Porquet et al. 1999) **# A high-ionization component of the inner narrow line region (e.g., Komossa & Schulz 1997; Ferguson et al. 1997; Binette et al. 1997) **# A low-density component of the interstellar medium (Korista & Ferland 1989) ** Photoionization by the central source is the main driving mechanism of the CL emission (e.g. Oliva & Moorwood 1990; Marconi et al. 1996; Kraemer & Crenshaw 2000b; Mazzalay et al. 2010) 'Bumps' in AGN SED # Big Blue Bump: (BBB: 3000-10000\AA; Sanders et al. 1989; Elvis et al. 1994; Richards et al. 2006) #* Thought to be the thermal radiation from accretion disk # Infrared Bump: (~10000\AA), accounts for 20-40% of the bolometric luminosity; #* Thought to be the thermal radiation emitted from a dusty torus located a~1 pc from the black hole (Sanders et al. 1989) # Small Blue Bump: (SBB: 2200-4000\AA); minor component that superimpose to the BBB #* is likely the blending of several iron lines and hydrogen Balmer continuum (Wills et al. 1985; Vanden Berk et al. 2001) # Synchrotron Bump: for radio loud AGN or powerful blazer, extending from radio to IR/optical wavelengths # Compton Bump: for powerful blazer, extending from X–rays to TeV energies Clustering of QSO * About a review of recent progress made on the studies of clustering of QSOs see (Shen et al. 2012) and the references within. ** QSOs lived in massive dark matter halo. ** Relative abundance of QSOs and their host halos can constrain the duty cycle of QSO. ** While galaxy show a strong dependence of clustering on luminosity, the QSOs do not. Scatter between the instantaneous quasar luminosity and host halo mass dilutes any luminosity dependence of the clustering. Observations of Galaxy Evolution Star-Forming and AGN * characterizing various global statistics of the high-redshift galaxy population, including their UV luminosity function, stellar mass function, and clustering properties (e.g., Steidel et al. 1999; Giavalisco et al. 2004a; Bouwens et al. 2007; Reddy & Steidel 2009; Ouchi et al. 2004a,b; Lee et al. 2006, 2009, 2012b; Gonzalez et al. 2011). In addition, the overall distribution of dust content, stellar population ages, and sizes have been determined at diﬀerent cosmic epochs (Ferguson et al. 2004; Bouwens et al. 2004, 2009, 2012; Stark et al. 2009; Reddy et al. 2006, 2012a; Lee et al. 2012a; Finkelstein et al. 2012) arXiv:1212.4835 * The star formation rate density (SFRD) in the Universe gradually increases toward z~3 from z>6, has a peak at z=1–2, and decreases sharply from z=1 toward z=0 (e.g., Lily et al. 1996; Madau et al. 1996; Hopkins & Beacom 2006; Sobral et al. 2012b) arXiv:1212.4905 ** At z=1-2, the star formation rate (SFR) in typical galaxies is an order of magnitude higher than in the local Universe (Reddy & Steidel 2009) ** The star formation rate density of the Universe peaks from z~1−3 (e.g., Bouwens et al. 2009; Magnelli et al. 2011; Murphy et al. 2011 ), an epoch in which the black holes within the center of massive galaxies are simultaneously building up their mass (Wall et al. 2005; Kelly et al. 2010 )arXiv:1212.2971 * The total star formation rate density, the rate at which new stars are being formed, has dropped by a factor & 10 (e.g. Wilkins et al. 2008; Zhu et al. 2009; Rujopakarn et al. 2010). A similar decline is seen in the total rate of accretion onto supermassive black holes (SMBHs), which is tracked by the luminosity density of Active Galactic Nuclei (AGNs) (e.g. Barger et al. 2005; Silverman et al. 2008; Aird et al. 2010). * The star-forming main-sequence: (Brinchmann et al. 2004; Noeske et al. 2007; Elbaz et al. 2007, 2011; Daddi et al. 2007; Pannella et al. 2009; Rodighiero et al. 2011; Karim et al. 2011; Sargent et al. 2012; Nordon et al. 2012; Magnelli et al. 2013) ** Deﬁned in the M∗−SFR plane, this main sequence (MS) represents the “secular” and dominant mode of baryon transformation into stars (e.g. Elbaz et al. 2011; Rodighiero et al. 2011; Wuyts et al. 2011b; Daddi et al. 2009, 2007; Elbaz et al. 2007) * The most massive galaxies appear to have older stellar populations than their less massive counterparts (Cowie et al. 1996; Bower et al. 2006; Gilbank et al. 2010) * Star forming galaxies at z~2 are a mix of "puffy" and often clumpy rotating disks, mergers, and more compact dispersion-dominated objects (Genzel et al. 2008; Shapiro et al. 2008; Cresci et al. 2009; Förster Schreiber et al. 2009; Law et al. 2009; Jones et al. 2010; Mancini et al. 2011) * The stellar mass function measures the comoving space density of galaxies of a given stellar mass, making it a powerful observational tracer of galaxy growth by in situ star formation, mergers, and galaxy transformations due to star formation quenching (e.g., Drory & Alvarez 2008; Peng et al. 2010). ** Measurements of the SMF are also important for connecting the physics of galaxy formation to the hierarchical assembly of dark matter halos, and large-scale structure (e.g., Conroy & Wechsler 2009; Cattaneo et al. 2011; Wang et al. 2012; Leauthaud et al. 2012; Behroozi et al. 2012). * At the highest redshifts, z>2, studies have shown that although quiescent galaxies exist, they are outnumbered by star-forming galaxies at all stellar masses (e.g., Whitaker et al. 2010; Dominguez Sanchez et al. 2011). **This early epoch is followed by a period of rapid growth in the space density of massive (>10^11M⊙) quiescent galaxies between z~2 and z~1 (Arnouts et al. 2007; Ilbert et al. 2010; Nicol et al. 2011; Brammer et al. 2011; Mortlock et al. 2011). ** By z~1, the stellar mass dependence of galaxy bimodality as observed locally is largely in place: star-forming galaxies outnumber quiescent galaxies at the low-mass end of the SMF, while quiescent galaxies dominate the massive galaxy population (e.g., Bundy et al. 2006; Borch et al. 2006). ** Subsequently, between z~1 and z~0, the transformation of star-forming galaxies into quiescent, passively evolving galaxies continues, leading to an approximately factor of two increase in the integrated stellar mass density of quiescent galaxies (Bell et al. 2004; Blanton 2006; Faber et al. 2007). *** The bulk of this stellar mass growth appears to be due to a rapidly rising population of intermediate mass (10^10 M⊙) quiescent galaxies, although the extent to which massive galaxies also grow through stellar accretion (i.e., mergers) remains controversial (Cimatti et al. 2006; Scarlata et al. 2007; Brown et al. 2007; Rudnick et al. 2009; Stewart et al. 2009; Ilbert et al. 2010; Pozzetti et al. 2010; Robaina et al. 2010). ** By the current epoch, quiescent galaxies vastly outnumber star-forming galaxies above 3*10^10 M⊙, and account for more than half of the total stellar mass in the local Universe (Bell et al. 2003; Baldry et al. 2004; Driver et al. 2006). ** It is not known why the stellar mass growth by in situ star formation balances—almost perfectly—the stellar mass growth of the quiescent galaxy population due to quenching (see, e.g., Arnouts et al. 2007; Martin et al. 2007; Peng et al. 2010) * In the high-redshift Universe the cold gas fraction in galaxies is higher than at low-redshift and thus there is more fuel for star formation (e.g. Tacconi et al. 2010; Geach et al. 2011). * The OII line is empirically calibrated and extensively utilised as a important SFR indicator for galaxies at z>1 (e.g., Kennicutt 1998; Moustakas et al. 2006; Gilbank et al. 2010) arXiv:1212.4905 * X-ray is efficient in identifying AGN from z=1-3 (e.g. Alexander et al. 2003; Brandt et al. 2001; Giacconi et al. 2002 ) ** X-ray spectra show majority of sources are obscured by gas and dust (see review by Brandt & Hasinger 2005 ) * Based on the presence of polycyclic aromatic hydrocarbons and continuum thermal dust emission, mid-infrared spectra can be decomposed into the relative contributions of SF and AGN activity (e.g., Laurent et al. 2000; Armus et al. 2007; Sajina et al. 2007; Pope et al. 2008; Kirkpatrick et al. 2012a ). *# At NIR: SF galaxy has a 1.6 micron bump from old population; AGN is pure power-law *# Dust temperature from FIR peak and shape: more warmer for more luminous AGN (Haas et al. 2003) * The AGN luminosity function provides the principal tracer of the distribution of SMBH accretion over the history of the universe. A variety of wavebands and identiﬁcation techniques have been used to measure the luminosity function of AGNs out to high redshifts (z<6) (e.g. Boyle et al. 1987; Page et al. 1997; Richards et al. 2006; Assef et al. 2011; Ueda et al. 2003; Ebrero et al. 2009; Aird et al. 2010). ** A number of studies have indicated that AGNs are preferentially found in the most massive galaxies (e.g. Kauﬀmann et al. 2003; Dunlop et al. 2003; Schawinski et al. 2007; Nandra et al. 2007; Coil et al. 2009; Hickox et al. 2009; Bongiorno et al. 2012). ** A number of more recent studies, however, have shown that AGN hosts have a similar distribution of colors to galaxies of equivalent stellar masses (e.g. Xue et al. 2010; Cardamone et al. 2010; Aird et al. 2012; Hainline et al. 2012; Bongiorno et al. 2012). arXiv:1301.1689 * The rotational transitions of the carbon monoxide (CO) molecule provide a direct probe of the excitation of the molecular gas in galaxies. Local starburst galaxies and ULIRGs (e.g. Bayet et al. 2004; Weiß et al. 2005b; Papadopoulos et al. 2007; Greve et al. 2009) and high redshift SMGs and quasars (e.g. Weiß et al. 2005a; Riechers et al. 2006; Weiß et al. 2007; Riechers 2011; Riechers et al. 2011) show signatures of excited molecular gas: observed CO line spectral energy distributions peak at Jupper > 5 with thermalized lines up to Jupper>3. ** In contrast, studies of the Milky Way (Fixsen et al. 1999) and local SFGs (e.g. Mauersberger et al. 1999; Yao et al. 2003; Mao et al. 2010) find a wide spread of excitation conditions, with an average that implies less-excited gas, where the Jupper = 3 line is already sub-thermal. LBGs, LAEs and LABs * These rarer, more extended, and more luminous objects are what we now call Lyman Alpha blobs (LABs) (e.g., Steidel et al. 2000; Francis et al. 2001; Matsuda et al. 2004; Dey et al. 2005; Nilsson et al. 2006; Prescott et al. 2012). LABs are extremely large (~30–200 kpc) radio-quiet Lya nebulae in the high redshift universe. ** There are currently three most widely discussed scenarios to explain both the large spatial extent and powerful Lya flux of these blobs. **# Heated by photoionization from massive stars and/or AGN (Geach et al. 2009). **# Heated by cooling flows / cold accretion (Haiman et al. 2000; Dijkstra & Loeb 2009). **# Overlapping supernova remnants from massive stars after a powerful starburst producing superwinds. (Taniguchi & Shioya 2000; Ohyama et al. 2003) * At z~3, the velocity offsets between resonance and non-resonance absorption features of Lyman-break galaxies (LBGs) (e.g.,Steidel et al. 1996; Adelberger et al. 2003; Shapley et al. 2003; Steidel et al. 2010) and the relative strengths and velocities of multiple-peaked profiles of Lya in emission (e.g., Verhamme et al. 2006; Tapken et al. 2007; Verhamme et al. 2008; Laursen et al. 2009; Barnes et al. 2011; Kulas et al. 2012) all point to outflows being common in these high luminosity systems. ** Outflows are also common in lower-luminosity objects: the spectral analysis of Berry et al. (2012) clearly demonstrates that Lya emitting galaxies at z~3 have strong galactic winds. * LAEs: most have SFR~2M_sun/yr and M*<10^9M_sun; These are the objects that will likely evolve into today L* galaxies like the Milky Way (Pirzkal et al. 2007; Gawiser et al. 2007; Guaita et al. 2010); LAEs are relatively metal-poor and dust-free, with internal extinctions A_V<0.5 (Gawiser et al. 2007; Guaita et al. 2010; Acquaviva et al. 2011) SMGs * The redshift distribution of the SMGs has a narrow distribution with a probable median redshift of 2−3 (Chapman et al. 2005; Aretxaga et al. 2007) ** Surveys at submillimetre wavelengths show that the SMG population has a sharp falloff at the bright luminosity end of their luminosity function. Gravitational lensing by intervening galaxy clusters and groups modifies the observed number counts significantly (Blain 1996; Lima et al. 2010b; Jain & Lima 2011; Hezaveh & Holder 2011). ** The cross section due to gravitational lensing may be affected by halo ellipticity (e.g. Rusin & Tegmark 2001; Huterer et al. 2005), the radial profile of the lens halo (Li & Ostriker 2002; Oguri & Keeton 2004) as well as the size of background galaxies (Perrotta et al. 2002; Hezaveh & Holder 2011) IGM and CGM * Observed correlation between absorption lines in background quasars and the projected distance (and velocity offset) to the associated galaxy: ** Low-Redshift ': ''Chen et al. 2001; Chen & Tinker 2008; Thom & Chen 2008; Yao et al. 2008; Chen et al. 2010; Prochaska et al. 2011; Thom et al. 2011; Tumlinson et al. 2011 ** '''High-Redshift: Simcoe et al. 2004; Steidel et al. 2010 Galaxy Formation Theory Models v.s Observations * Cooling Crisis: Gas cools radiatively during the hierarchical buildup of the halo population and condenses to form galaxies in halo cores, results in more massive galaxies than observed (Balogh et al. 2001; Lin & Mohr 2004; Tornatore et al. 2003 ) ** Additional source of non-gravitational heating to prevent a cooling crisis (White & Rees 1978; Cole 1991; White & Frenk 1991; Blanchard et al. 1992 ) ** Stellar feedback seems not enough (Borgani et al. 2004 ) ** People started considering AGN feedback (Churazov et al. 2002; Springel et al. 2005a; McNamara & Nulsen 2007 ) *** Which resulted in the improvement on: ***# luminosity-temperature relation of X-ray clusters (Valageas & Silk 1999; Bower et al. 2001; Cavaliere et al. 2002 ) ***# luminosity function of galaxies (Croton et al. 2006; Bower et al. 2006; Somerville et al. 2008 ) arXiv:1212.4131 Inter-Stellar Medium * HI has long been the best tracer of Dark Matter (DM) in galaxies (e.g. Bosma 1981; van der Hulst et al. 1993). ** Typically the projected DM surface density scales very well with the measured HI surface density (Bosma 1981; Sancisi 1983; Carignan & Beaulieu 1989; Carignan et al. 1990; Carignan & Puche 1990a,b; Jobin & Carignan 1990; Broeils 1992; Meurer et al. 1996; Hoekstra et al. 2001). arXiv:1212.1502 IGM and CGM * Cold and hot-mode accretion (e.g. Binney 1977; Birnboim & Dekel 2003; Keres et al. 2005; Ocvirk et al. 2008; Keres et al. 2009; Faucher-Giguere et al. 2011; Van De Voort et al. 2011 ) ** Observational identification of these cold stream could be hard due to low covering facter (3%-10% at z~2) (e.g Faucher-Giguere et al. 2011; Kimm et al. 2011 ) ** The cold streams at high-redshift contribute significantly to the observed population of Lyman-limit systems (Fumagalli et al. 2011 ) * From the observed mass-metallicity relation and enrichment of the IGM, it is also clear that the baryons must have at one point entered galaxy halos and disks and been enriched, then were ejected (Tremonti et al. 2004; Erb et al. 2006; Aguirre et al. 2001; Pettini et al. 2003; Songaila 2005; Martin et al. 2010) arXiv:1301.0841 Magnetic Field in Galaxies * In galaxies, magnetic fields are suspected to be particularly important as here the magnetic pressure in the inter-stellar medium (ISM) becomes comparable to the thermal pressure. Magnetic fields may hence be dynamically relevant for the evolution of galaxies (Beck 2009) arXiv:1212.1452 * The structure and strength of magnetic fields in galaxies determines the propagation of cosmic rays (Strong & Moskalenko 1998; Narayan & Medvedev 2001) * Magnetic field strengths have been measured for a number of galaxies using: *# Zeeman splitting in maser emission (Robishaw et al. 2008) *# Radio Polarization measurements (Beck 2007) * The formation and amplification of magnetic field during galaxy formation (For recent review: Kulsrud & Zweibel 2008) ** Weak initial magnetic field could be cosmological origin, or were created by Biermann batteries. ** Further amplification can then proceed through: **# Structure formation flows (Dolag et al. 1999) **# Galactic Dynamo (Hanasz et al. 2004) **# Turbulent amplification (Arshakian et al. 2009) Extragalactic Background Light * The extragalactic background light (EBL), the diffuse, isotropic background radiation from far-infrared (FIR) to ultraviolet (UV) wavelengths, is believed to be predominantly composed of the light from stars and dust integrated over the entire history of the Universe (see Dwek & Krennrich 2012, for reviews). arXiv:1212.1683 ** The observed spectrum of the local EBL at z = 0 has two peaks of comparable energy density. The ﬁrst peak in the optical to the near-infrared (NIR) is attributed to direct starlight, while the second peak in the FIR is attributed to emission from dust that absorbs and reprocesses the starlight. ** Measurements of EBL zt z~0 in optical and NIR is hampered by zodiacal light (Hauser & Dwek 2001); but see Matsuoka et al. 2011 for measurement from Pioneer 10/11. ** Integration over galaxy number counts provide a ﬁrm lower bound on the EBL, and the observed trend of the counts with magnitude indicates that the EBL at z = 0 has been largely resolved into discrete sources in the optical/NIR bands (e.g. Madau & Pozzetti 2000; Totani et al. 2001; Keenan et al. 2010) ** The EBL can also be probed indirectly through observation of high-energy gamma rays from extragalactic objects (Mazin & Raue 2007) *** Observations of blazars by current ground-based telescopes have been able to place relatively robust upper limits to the EBL at z=0 and up to z~0.5 (e.g. Aharonian et al. 2006a; Albert et al. 2008). ** Theoretical Models for EBL: **# Backward evolution model: Malkan & Stecker 1998; Totani & Takeuchi 2002; Stecker et al. 2006; Franceschini et al. 2008 **# Forward evolution model: Kneiske et al. 2004; Finke et al. 2010 **# Semi-analytical Models of Hierarchical Galaxy Formation * The EBL in the X-ray, or cosmic X-ray background (CXB), is now known to be the relic emission of cosmic supermassive black hole (SMBH) accretion (e.g. Comastri et al. 1995) arXiv:1212.3642 Really High-Redshift Universe * Molecular hydrogen has been invoked as a signiﬁcant coolant of primordial gas leading to the formation of ﬁrst stars and galaxies (e.g. Haiman 1999; Bromm & Larson 2004; Glover 2005; Glover 2012 ) arXiv:1212.2964 Galaxies in Really High-Redshift * About the recent development in the luminosity function of galaxies at z~7-8, see Schenker et al. 2012 (arXiv:1212.4819) for a review. This work is based on HUDF12 results. * There is now overall evidence for the mass build-up of early galaxies at z~4-8 based on the evolution of the cosmic star-formation density (Giavalisco et al. 2004, Bouwens et al. 2004, 2007, Bunker et al. 2004, McLure et al. 2006, 2009, Yan et al. 2006, 2010, Castellano et al. 2010, Oesch et al. 2010b) arXiv:1212.1448 * A wider variety of results have been obtained on the ultraviolet spectral slopes and stellar populations of these early star-forming galaxies at z~7-8 (Bouwens et al. 2009, 2010, 2012, Ono et al. 2010, Bunker et al. 2010, Finkelstein et al. 2010, 2012b,a, Yan et al. 2011b,a, McLure et al. 2010, 2011, Grazian et al. 2011, 2012, Bradley et al. 2012, Dunlop et al. 2012a,b) arXiv:1212.1448 Reionization * About the calculation of escape fraction in high-z galaxies, see Benson et al. 2012 * The Gunn–Peterson test, in which a non-trivial ion fraction creates a trough by line absorption at every redshift (Gunn & Peterson 1965), is the most direct test of the later stages of helium reionization. arXiv:1212.1502 * Existing cosmological observations show that the reionization history of the universe at z > 6 is likely both complex and inhomogeneous (e.g. Haiman 2003; Choudhury & Ferrara 2006; Zaroubi 2012 ) ** When does the reionization started: from the polarization signal of the CMB anisotropy power spectrum, the total optical depth to electron scattering suggest it started around z_{ri}=11 ( Komatsu et al. 2011 ) * Other possible probes: *# 21-cm HI spin-flip line: Madau et al. 1997; Loeb & Zaldarriaga 2004; Santos et al. 2005; Santos & Cooray 2006; McQuinn et al. 2006; Bowman et al. 2007; Mao et al. 2008 *# Line emission associated with atomic and molecular: *## CO: Gong et al. 2011 *## CII: Gong et al. 2012a *## Lyman-alpha: Silva et al. 2012 *## H_2: Gong et al. 2012b (astro-ph:1212.2964) ** More sensitive to the late stages of reionization (Righi et al. 2008; Visbal & Loeb 2010; Carilli 2011; Lidz et al. 2011 ) * The reionization epoch of singly ionized helium (He II) is believed to start at redshifts z~3.5–4 and be nearly complete by z≃2.7 (Furlanetto & Oh 2008) ** delayed because of the need for high-energy photons than stars provide (E>4 ryd) ** This is consistent with redshift estimates from the intergalactic medium (IGM) temperature (e.g., Becker et al. 2011), which increases noticeably during helium reionization, as well as estimates from the redshift evolution of the He II Gunn–Peterson optical depth (e.g., Syphers et al. 2011a, 2012; Worseck et al. 2011; but see Davies & Furlanetto 2012) arXiv:1212.1502 Population III * Coincidently, the footprint of both PopIII star formation and gas cooling during gravitational accretion is the presence of Lyαλ 1216 and HeII λ 1640 emission lines in the spectra of the sources. Dual Lyαλ 1216 and He II λ 1640 emitters have been proposed by various authors as candidates hosting PopIII star formation (Tumlinson et al. 2001; Schaerer 2003; Raiter, Schaerer & Fosbury 2010) arXiv:1212.5270 ** Strong Lyα+He II emission lines are commonly found in other astrophysical objects, such as Wolf-Rayet stars (W-R), AGN and supernovae driven winds. However, several diagnostics can be used to distinguish cooling radiation and PopIII star formation from these other mechanisms: AGN, W-R stars and emitters powered by supernovae driven winds typically show other emission lines in their spectra, such as CIII and CIV (Reuland et al. 2007; Leitherer et al. 1996; Allen et al. 2008). ** Moreover, W-R stars are associated with strong winds, and thus produce broad emission lines (a few 1000 km/s, Schaerer 2003) ** Brinchmann, Pettini & Charlot (2008) showed that the broad He II emission detected in the composite spectrum of z~3 galaxies by Shapley et al. (2003) can indeed be reproduced by W-R models. ** Nebular He II emission also appears in some star forming regions in which the source of ionisation is not clearly identiﬁed as WR or O stars, but this is a rare event in the local universe (Kehrig et al. 2011) * The high Jeans mass of metal-free gas suggests a top-heavy IMF (Abel et al. 2000; Bromm et al. 1999; Abel et al. 2002; Yoshida et al. 2003) for Population III stars (Pop-III) arXiv:1212.1157 * Pop-III stars may lead to the occurrence of pair instability supernovae (PISNe) (Heger & Woosley 2002) arXiv:1212.1157 HST Deep Fields * Hubble Deep Field (Williams et al. 1996) * Hubble Deep Field South (Casertano et al. 2000; Williams et al. 2000; Lucas et al. 2003) * Ultra-Deep Field (Beckwith et al. 2006; Thompson et al. 2005) ** Following programs in 2005, PI.: M. Stiavelli, see Oesch et al. 2007; 2009 ** WFC3/IR follow-up in 2009, PI.: G. Illingworth, see Oesch et al. 2010a,b; Bouwens et al. 2011b ** UDF12, PI.: R. Ellis, see Ellis et al. 2012; Koekemoer et al. 2012 Other Shallower HST Surveys * GOODS: (Giavalisco et al. 2004) * '''GEMS' : (Rix et al. 2004) * '''AEGIS': (Davis et al. 2007) * '''COSMOS': (Scoville et al. 2007; Koekemoer et al. 2007) * WFC3 ERS: (Windhorst et al. 2011) * CANDELS (Grogin et al. 2011; Koekemoer et al. 2011) * BoRG: (Trenti et al. 2011) * HIPPIES: (Yan et al. 2011b) * CLASH: (Postman et al. 2012) The Large-Scale Structure and Cosmology Clustering of Galaxies * First statistical studies of galaxy clustering: (Totsuji & Kihara 1969; Peebles 1973; Hauser & Peebles 1973, 1974; Peebles 1974 ) found the galaxy correlation function behaves like a power law, which is difficult to explain from first principle (Berlind & Weinberg 2001 ) ** Recent studies found deviations from a power law (Zehavi et al. 2005a),, and the deviation can be explained by a 3-parameter Halo Occupation Distribution model (e.g. Jing, Mo & Borner 1998; Ma & Fry 2000; Peacock & Smith 2000; Seljak 2000; Scoccimarro et al. 2001; Berlind & Weinberg 2001; Cooray & Sheth 2002 ) ** This deviation (a dip in the Correlation Function at 1-3 h^{-1} Mpc) can be explained by the transition from the 1-halo to 2-halo term in the HOD model. ** The deviation is larger for highly clustered bright galaxies (Zehavi et al. 2005a,b; Blake, Collister & Lahav 2008; Zheng et al. 2009; Zehavi et al. 2010 ), and at high redshift (Conroy, Wechsler & Kravtsov 2006 ), which agrees with theoretical predictions (Watson et al. 2011 ). arXiv:1212.3610 * HOD modelling has been applying to galaxy clustering data from : *# 2dFGRS: (Porciani, Magliocchetti & Norberg 2007; Tinker et al. 2006 ) *# SDSS : (van den Bosch, Yang & Mo 2003; Magliocchetti & Porciani 2003; Zehavi et al. 2005a,b; Tinker et al. 2005; Yang et al. 2005, 2008; Zehavi et al. 2010 ) *# VVDS (Abbas et al. 2010); Bootes (Brown et al. 2008); DEEP2 (Coil et al. 2006); LBGs in GOODS (Lee et al. 2006) * The measurements of the cosmological parameters heavily rely on accurate measurements of power spectra. Power spectra describe the spatial distribution of an isotropic random ﬁeld, deﬁned as the Fourier transform of the spatial correlation function. arXiv:1212.3194 * The dependence of galaxy clustering on galaxy properties has been observed in numerous galaxy surveys (e.g., Davis & Geller 1976; Davis et al. 1988; Hamilton 1988; Loveday et al. 1995; Benoist et al. 1996; Guzzo et al. 1997; Norberg et al. 2001, 2002; Zehavi et al. 2002, 2005b, 2011; Budav´ari et al. 2003; Madgwick et al. 2003; Li et al. 2006; Coil et al. 2006, 2008; Meneux et al. 2006, 2008; Wake et al. 2008; Swanson et al. 2008; Meneux et al. 2009; Ross & Brunner 2009; Skibba et al. 2009; Loh et al. 2010; Ross et al. 2010, 2011a; Wake et al. 2011; Christodoulou et al. 2012; Mostek et al. 2012) arXiv:1212.1211 * The subhalo abundance matching (SHAM) method makes use of subhalos in high resolution N-body simulations and connects them to galaxies to interpret galaxy clustering (see, e.g., Kravtsov et al. 2004; Conroy et al. 2006; Guo et al. 2010; Nuza et al. 2012). arXiv:1212.1211 * The halo occupation distribution (HOD) framework (see e.g., Peacock & Smith 2000; Seljak 2000; Scoccimarro et al. 2001; Berlind & Weinberg 2002; Berlind et al. 2003; Zheng et al. 2005) or the closely related conditional luminosity function (CLF) method (Yang et al. 2003, 2005) describe the number of galaxies as a function of halo mass, and galaxy clustering is used to constrain the HOD or CLF parameters. arXiv:1212.1211 Weak Lensing * Weak gravitational lensing by large-scale structure provides valuable cosmological information, especially since weak lensing is sensitive to the distance-redshift relation and the time-dependent growth of structure, it is a particularly useful tool for constraining models of dark matter. (Bartelmann & Schneider 2001; Albrecht et al., 2006; Peacock et al., 2006; Albrecht et al., 2009 ) ** To constrain the dark energy, lensing signal must be measured at several redshifts--the so called weak lensing tomography (Hu 1999; Huterer 2002; Bacon et al. 2005; Semboloni et al. 2006; Massey et al. 2007; Schrabback et al. 2010 ) Cosmic Microwave Background * At z=0, T_0=2.72548\pm0.00057 K (Fixsen 2009) * Studies of the cosmic microwave background (CMB) have dramatically progressed over the past two decades (e.g., Smoot et al. 1992; Cheng et al. 1997; Baker et al. 1999; Miller et al. 1999; de Bernardis et al. 2000; Knox & Page 2000; Hanany et al. 2000; Lee et al. 2001; Romeo et al. 2001; Nettereld et al. 2002; Halverson et al. 2002; Kovac et al. 2002; Carlstrom et al. 2003; Pearson et al. 2003; Scott et al. 2003; Benot et al. 2003; Spergel et al. 2003; Johnson et al. 2007; Chiang et al. 2010) * The current generation of arcminute resolution cosmic microwave background (CMB) experiments is providing researchers with a precise view of CMB anisotropies over a range of scales (500 < ℓ < 10000). ** Over the so-called Silk damping tail of the CMB (500 < ℓ < 3000) these observations are revealing the subtle eﬀects that inﬂationary physics, primordial helium density and the energy density in relativistic degrees of freedom have on the acoustic oscillations in the photon-baryon plasma in the radiation-dominated era. ** On smaller scales (ℓ > 3000) the primordial CMB signal diminishes and emission from radio galaxies and dusty star forming galaxies, as well as the thermal and kinematic Sunyaev-Zel’dovich eﬀects (Sunyaev & Zeldovich 1972) arising from the scattering of CMB photons by hot gas in galaxy clusters, dominate the power spectrum.arXiv:1301.1037 Measurement at high-redshift * Measuring the CMB temperature at high redshift has considerable cosmological interests, in: *# Demonstrating that the CMB radiation is universal (Equivalence principle) *# Tracing the evolution of its temperature with redshift, T_{CMB}(z) . Adiabatic expansion predicts that the CMB temperature evolution is proportional to (1+z). Alternative cosmologies, such as decaying dark energy models (e.g. Lima 1996; Lima et al. 2000; Jetzer & Tortora 2011) where dark energy can interact with matter via creation of photons, aﬀecting the CMB spectrum. ** Two methods can be used to probe the CMB temperature at z>0. **# The ﬁrst one is based on multi-frequency Sunyaev-Zeldovich (S-Z) observations toward galaxy clusters (see e.g. Horellou et al. 2005; Battistelli et al. 2002; Luzzi et al. 2009; de Martino et al. 2012) **# spectroscopic studies of lines in absorption against quasars and their excitation analysis. Most of the measurements at high redshift have used UV spectroscopy of atomic species (CI: Meyer et al. 1986; Songaila et al. 1994b; Ge et al. 1997; Roth & Bauer 1999; CII: Songaila et al. 1994a; Lu et al. 1996; Molaro et al. 2002; CI & CII: Srianand et al. 2000) *** Strictly speaking, these measurements are all upper limits on T_CMB, as the contributions from other local sources of excitation (collisions, local radiation ﬁeld) are yet largely uncertain and poorly constrained, and have to be accounted for. S-Z Effect of Galaxy Cluster * Within the last few years, cluster surveys exploiting the Sunyaev-Zel’dovich effect (SZ; Sunyaev & Zel’dovich 1970) have also begun to deliver cluster samples (e.g., Staniszewski et al. 2009; Marriage et al. 2011; Williamson et al. 2011; Planck Collaboration 2011a; Reichardt et al. 2012b) and constraints on cosmological parameters (Vanderlinde et al. 2010; Sehgal et al. 2011; Benson et al. 2011; Reichardt et al. 2012b). ** Since the SZ signal is not diminished due to luminosity distance, it is nearly redshift independent; in principle SZ surveys can detect all clusters in the Universe above a mass limit set by the survey noise level (e.g., Birkinshaw 1999; Carlstrom et al. 2002). ** Although current SZ cluster samples are small in comparison to existing X-ray and optical cluster catalogs, they provide very powerful complementary probes because they are sensitive to the high mass, high redshift cluster population (e.g., Brodwin et al. 2010; Foley et al. 2011; Planck Collaboration 2011b; Menanteau et al. 2012a; Stalder et al. 2012). Simulation of Galaxy Formation Tidal Stripping and Merging * When dark matter haloes merge, these protogalaxies also merge; depending on the mass ratio the satellite galaxy can either rapidly merge with the central object or orbit around it for a consistent amount of time (e.g., Chandrasekhar 1943; Binney & Tremain 2008; Jiang et al. 2008; Boylan-Kolchin et al. 2008 ) ** About the possible progressive mass loss, both in dark matter and stellar component (e.g. Mayer et al. 2001a; Klimentowski et al. 2007; Penarrubia et al. 2008; Kazantzidis et al. 2011 ) ** N-body simulations about this topic: (Moore et al. 1999; Gnedin 2003; Mastropietro et al. 2005; Mayer et al. 2001a, b; Klimentowski et al. 2009a; Kazantzidis et al. 2011; Villalobos et al. 2012; Chang et al. 2012 ) arXiv:1212.3408 * Environmental effects (e.g. tides and stripping) have an important role in shaping the properties of the local dwarf spheroidal galaxies (e.g., Einasto et al. 1974; Faber & Lin 1983; Mayer et al. 2001a, 2001b; Kravtsov et al. 2004; Mayer et al. 2006, 2007; Klimentowski et al. 2007; Penarrubia et al. 2008; Klimentowski et al. 2009a, 2009b ) * Using this new MHD code (+AREPO), we simulate the formation of isolated disk galaxies similar to the Milky Way using idealized initial conditions with and without magnetic fields. We found that the magnetic field strength is quickly amplified in the initial central starburst and the differential rotation of the forming disk, eventually reaching a saturation value. At this point, the magnetic field pressure in the interstellar medium becomes comparable to the thermal pressure, and a further eficient growth of the magnetic field strength is prevented. The additional pressure component leads to a lower star formation rate at late times compared to simulations without magnetic fields, and induces changes in the spiral arm structures of the gas disk. arXiv:1212.1452